1. Field of the Invention
The present invention relates to a semiconductor device using a case and to a method for manufacturing the same.
2. Description of the Background Art
In general, a casing type power semiconductor module is formed of separate components which are an internal lead terminal inside the power semiconductor module and an external lead terminal provided in a tube part as a portion of the case (for example, see Japanese Patent Application Laid-Open No. 2007-081155).
Specifically, the internal lead terminal is connected to semiconductor elements disposed on a base plate (supporting member) by means of soldering and the like. Moreover, ends of the internal lead terminal are primary connected to a relay section in the power semiconductor module. Next, the tube part of the case is fixed to the base plate by an adhesive and the like, and the external lead terminal is secondary connected to the relay section. Thus, this structure is able to provide continuity between the semiconductor elements and an external connection terminal.
Furthermore, a general structure is that after assembling it as mentioned above, a sealing material is injected to seal the internal of the power semiconductor module.
However, the structure of the power semiconductor module as mentioned above has a great number of components, resulting in an increase in complexity. To solve the problems above, Japanese Patent Application Laid-Open No. 2006-093255 discloses a technique (hereinafter, referred to as a related technique A) for directly connecting a lead terminal (lead frame) integrated into the case to a semiconductor chip.
However, the related technique A has problems. Specifically, in the related technique A, for example, when pressure is exerted on the lead terminal and thus the lead terminal generates a great stress (resistance) in a manufacturing process, the lead terminal may become deformed in some cases. In this case, a malfunction resulting from the lead terminal may occur such that the semiconductor device serving as the power semiconductor module does not operate properly.